SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '035a70afe0e668932f5b1585d6acc368310f7aae18b4b7292b4a6001169971d5' 
  AND token = 'z2N/LGZYDxt7tBbVQYBjQz4VR+8q16JFlLjYpO1JaXc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

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