SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '71e2aa5d04d79289e127cca80649af6c3a9f28799e35bfaa771f30fb10a2359d' 
  AND token = 'DIy9mVAigsP7nLwKzdnmOs0hOZPKgsRyEpQ8w0ibBPc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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