SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8fb837cdab3e07a96d43d69d389bc9f317a8d6d597477229ea52b9b0e1fc5bb9' 
  AND token = 'HO5GqTsW7UPpo/GZjfGB1qPBJ86+Qx7IeZILowRRxfg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}