SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3041c5be043fd84b4de15b1f60522a5f5daa200c8e575f04eb9cb822b0d0585' 
  AND token = 'TZVXc2Wplj6OfJJv1ZNPZQOjR4xj644uqpreZjs9byc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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