SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f7d616b9f422bbb0f5e9c5319877283cdf3f8accf95bba05bfe9c5be2b24b61' 
  AND token = 'HiPUW3VK8rAbSGv/UxeFm/V3N4MIYKD+1/vw6ZcCCCY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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