SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '428960cb8931b3817b33183d5e01f9baf3d6760ed48fd155dddaa73cb1a0c051' 
  AND token = 'oOagP1uG++85MmcdcUdxbY3RDOQsBTySFC2qpXeh66c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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