SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'db5d99dcedfad33dcf025a47a5aae0d0ca745a73f745d93bc7b18ed2e9487cc4' 
  AND token = 'pvV3v5aqEdfVNY2nMkoMdh0Na9AlubvSFnE07pED8qs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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