SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3d3fe0ad44a0685ca145b7c69a1175176a899f5e086f50fd4de882acd511e4c4' 
  AND token = 'iuW3LueG2HuWz2R+yKk88GwEAb/kAoo5llyvHJx7YtA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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