SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97c026f103d6a1806d5b46c816cb4aa4ea19b60594b3710c683166f7a6c9cbb2' 
  AND token = 'ACyPLghuDVarx5HOMWO5xkEf83ikKVBeW/pNN5rVT7Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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