SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3e451d638ae0acf3ddd0571fcdf7a745002e716820baa512c37967adcfeccdfe' 
  AND token = 'NY80UU3yzYVkXAqtIB7W5juQS5cXdx5KexD3lECcgJc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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