SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5fc68098c13972c30eac7205c84ade0d0feedb7a3ca65c9aaa65b0a169bd8187' 
  AND token = 'Zm0sFoSrbq7/fsGbCRpRq1tj8w0NjqnywxB/p5bf5mQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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