SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b6833dbec33e4ddb471ee8ad34bb58127f24d70f98b4327f394f1b98744229aa' 
  AND token = 'jnWyg29jyJG7GxbABUZ46/4/vCrLHEusNoqXr5G3y1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00034

JSON explain

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