SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33d4973f89aa87a4b2841aa9ff51cca4c45783dc3b167ec91ab2a3b4851ebf3a' 
  AND token = 'sfiG1n1fywZOyBjs2kPQRBh0Z5pjCilEcBal7ar/E4o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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