SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '86bb6d102203c097f907aee4cf9527fdd1f0f345fb44eeab020d97ea9915c18e' 
  AND token = 'aUKF5f2nPLdGSAA2Vdtqf7XbjHYK0JbPC8imbJQeyIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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