SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27db8aa704048d9f4c753a1bf83473ab57e614306c9cbca2358f1ffa8eaa3023' 
  AND token = 'b4CPHSXMXQ+2kR18Xez7kXCdPxoczOCTpUGHsYp8GS4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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