SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '73127b773ec45a0075f7069c2ee29d64e2c768c10d2677ad8666c683967e412a' 
  AND token = 'BJdw3tx5MPWmJW5ZFXrvMlme80YyVCFx2SaAPPpKX2I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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