SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '48389942e2b7d5cb9b096d3c199b4ca7e55ed6abca29d8c8924cfadf60ac78fc' 
  AND token = 'AFQi9PL/ihDf6tD+DhFGZ7AYaUKBkLlPbUx/G1n9S3I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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