SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e6f8c5bf7135347a83d68a324f3af88dc9ee2e49e6c86c135cc9a4365644f4af' 
  AND token = '4ThmSlvG8l2/emuYj2OXrDPv263xCbn4H/asEBaeI4I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

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