SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bba0ea3ddfe7b006d66713e4ab15448eabb1e574954a717bf2e85d0371978d47' 
  AND token = 'wmtLiLVKch8EsRJUoYwsH5C5EFiLilGv+CM0pXJ8eUI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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