SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '67bc902074753f0d17bd8f42c4a9ef33c71a5f135023acc87a6fdb74ed768104' 
  AND token = '/EHg+SziaK4jw6PZTM/w9GgSvWB+Y2zgm0a+mywRbWk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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