SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79533c77a89a2f458b5c6d37872140bcaa2fb872cbeb8161bad87803150986a3' 
  AND token = 'SMVYE1aBGRaqSm2eagaFw0qqfEVkDHzZMnXZAlGCy4s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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