SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2fbb31c33c258ee1bcb6fc2b3bd68d08af5d332e77a977e607c8e2eaea712ae2' 
  AND token = 'AvQjyWH9qGrhhPKnggGr5zvxq6OBHFNOmXVj/9PkrG4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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