SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0732349b7baa01be0fdef4c0997eca21f6c88fcd45e4c9ea180cd8275478c017' 
  AND token = '7wWa4mT407SSeVDhBb1uISVjyi6kDRGzbSCwym022Lk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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