SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '29579a5e6c719b16a887d53fd65c7f5d63716b7e64f1bcb16d205bca69a70515' 
  AND token = 'CsgZTz0GCwZj6ldJ3nTSUrGxuf4wbJK/bmqf+lH3fx0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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