SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b347375193d6b18d28b8f6817e4d6309be0393dcac440dd0887a3c5632588b5' 
  AND token = 'iIB3X/X7GUysnpCuSA2vigMX2kO8NkL8F0+zDYMi/io=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00015

JSON explain

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