SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b23d665b3165e02b668450dbf5335d52267c109eb4f17326f9f500fe3d1ccfa' 
  AND token = '69CofRgNYaUyYFbEv859ynfUjxkqbaC0iZfvRACSo4g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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