SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2b0464d75a2d227f33c3b8ae0b11df744e8f01762f7cb02453189860db1a5abe' 
  AND token = 'CqZGxiChHa3c+nunpqrwv5uRpCLP+tCSXJm2nNTzAIw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

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