SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd465f15b94be11dad27f5890de89cc034e717015ebdcca160f2791b358c83a20' 
  AND token = 'PZ4b6FoOjpG1E2nIZQ3z7reuk9tSjyjQMFur8lHdzH4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}