SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9fdfe235cb8c2c52b7d1c53cc6c14ebbc6084f0699ec3cc5a3be338549b9a809' 
  AND token = 'dVE8BiQl60LiQiyKYu08OdnN0WVwZbfMskawugpITOs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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