SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2183c4bd8c26926731fdfcebf66cd89ff7f81614015fda109e93174116869b7' 
  AND token = 'zISxUOGYUx7eXPml2/siBEpDD4KjMFMZ3JRUUwiPSN8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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