SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ca0702b58e8b5c791926916624698cfb6193ce6292094ad72fa3a8ce85490abb' 
  AND token = '9FSjDXRIkBvjl09rlXjuIhFZd8LVmoJq/NmxO2YJNfI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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