Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac21652cbf5f877a64a0c1745c68ad08075e5d6ef5ff997ba3b669399537673f' 
  AND token = 'uMLtpY2LIXXV+hiy5sCfYWhPWs+3QgSz5a9HxDrncWg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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