SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dd7abcb3c3e589906d22e0a46d743f8bd7145c6586e748dfa2d181d266c59574' 
  AND token = 'AKBWvLZ5+bCpkN4WuWs7BozFrCfAIABUT5Pq89d2AzM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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