SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e13c55de68395b312b7f7560fa78b35837140dc7aa8ed178d8383249e58f3819' 
  AND token = 'sjM8GGFYeBxzmYr1DO5DIph+DqmH6Va3ma0voilc1IU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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