SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b956d5715349089234926a6ac51a541edabc8c974772aae51330380aea2fb6ef' 
  AND token = 'Z+deOpNKs/WO06mfmq43u5kmTrG0il5Wm236b+BztZs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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