SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff0b24ee0a2f0a043145350be9d29309092e9085418a9ecc274e70ffd6061853' 
  AND token = 'W914MzuYDSKQTVJvjFG+IMNRQwSAGn7Ky/ZKM3M4cHY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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