SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d160c54084984aeddb034cca0676ebc021e607677e69d7aab2f576b48e68d3a' 
  AND token = 'mYZMdw2H4Warrq4wbY5bL/W78zXnHYzlA1kjKIpS+Qk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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