SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f17c47527311137b5a517af499676ece16991bc945982f18bdfcadb9443421a6' 
  AND token = 'bhzNZ5RvfqhAcUZivEAhtK1Gz7gSwjnoszHX7l9bjQM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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