SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3ec7b7d55e96435b034d6a746b7b9a91ada05bcf17db73ae7acb5267a8eefb25' 
  AND token = 'hSqcbsAxK35g2cMDd/k172Boxjf/BkQulM7SdsPyBsI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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