SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '17e568982095599e4ba2f52121f95965973ea26f6d24b46a2a4fd91fdc151b63' 
  AND token = '952sxgKLxig/JD+sSS3WYU0eItUQ+/2/rzVPNmw3NGA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00023

JSON explain

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