SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8443587d5cbef988edd16e44ab72a659f34d4cacef9fa870a393ff9d282d0005' 
  AND token = 'AgFyqkvccgFQ8Ns/AdFGzc0uUlCKT6+JpiCHR58WwPg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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