SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ed40298c4bc31178a165e4cb846131a2bc09a0a58a38b4f30c7725c2385d4de7' 
  AND token = 'sZBjXpQ/9JcUGwAQZpLmR3l3TWadHRsvWYjwrJkWLOA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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