SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '133391d15cb97ecb44e6341e86b5cb523132e290dec3e67e31c1960f7d38ddac' 
  AND token = 'kiQvx3CBQWk/3OdH1qkSDxua5b4tQNTfMeBcEwkOWWs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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