SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd09ffb011ac7034296bbccbd660e43c1b53a722c05c3346997ef804b96e53d50' 
  AND token = 'JLiA7JqJuF94PY+mwlo5YYryQFqQ/vZ87u+y9BG7SPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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