SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'af85b663e2930191bf5f9c6057cdbf0faaf90fcdae7f26d36306636a778aec59' 
  AND token = 'ZAgxGAGHO8w+6NRybXd8edoyRRajDndRU/e14/1T5vI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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