SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1e9ba9edeface0b60df557edb753e0270a952b8ef426d53576ac10f0bee34800' 
  AND token = 'nY+OLqsEn7lUrUuO+OZ6oAfMb9HRSb1Cm8EPiK8ZLOc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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