SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2fa6a94315a655ee24a0d3b7eb713b9f4297a40439fc7f7783a8f4cce648590' 
  AND token = 'J43SnWDOivuNd0l71sOLiXtXulqjUGJUkNDrdkoszSQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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