SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7c60e6ecadb0fcb013c0a27df7ba420de91003d46ee4b6e414f54ea15155966f' 
  AND token = 'FPtrazFRkpxZTQK/mw5/ohoM0eV0SUlWM6EoATJSD4Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}