SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2d9cf6ec2445b04f33cae87999780a2ea7c72446ff60172c5621037c59584a82' 
  AND token = 'eDRttESwKGd/v2xHhjj904aBqzRLxkjBAKzPSqZetHM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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