SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'caa26390ca823c2445612229add2be6e6af8dc88f8776a25d0a8e74347e44d9f' 
  AND token = 'UY0hLoigBhnp3lK6j7Fafu0S7tA9VdazI3QUjjrtZrM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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