SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0ec881d96946f8f2f20663f39f4d30fe4915a4b3bcfd193f20a8fcab085f36fb' 
  AND token = 'FfTugocfUKk1BRvbSnQowT8va61nXgoHnufBAIEull4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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