SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '05fc1da69829e048ab53b39d6f6bcaadf58ee7a309bc5ad7ee53d85e2198d352' 
  AND token = 'Ry4pW0+lOMaxk4QZ/FI9iEmXMcAH3EnCUc2RcqcZMuI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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