SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8486dac41151b464f3432bafc3a5c3583d698588d6b0223740bd2d99d35d09ff' 
  AND token = 'N9VxKc2mkzlsYRFUJonfN4fx9Lwx5IqUA4a4q7PVUjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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