SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9f924aadfd2e5de007a2603a49ad1990d4293ff701ca896b8be29f791f739d06' 
  AND token = '0YxJrgfzeZSoc777An3/PTFoLEm6PtsOuXAHiqzl0cc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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