SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '724af0dded3e3378d33557adbbc7d92257c9bb1fdfdbfdf0fcbc22fe83787101' 
  AND token = '3SVRurdElwH2TjdiuEcd+irVumc3RV2HwwR6UDP0lPE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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