SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a9aaf59259f9bed3e46ad1aeb3f5a5ff5c985dce75d275d270634f32ad923e69' 
  AND token = 'JapItFp1R1MjWOYMpur6jMSCI6UXR4mZaFCN+2CGHbc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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