SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df239672fd469781232c3e8bae4090f1c871052158d64f37dd9512cc42eb419a' 
  AND token = 'Yw2PYf+uRv2FK7Vk9lAFdbmz4zxkBa3T+4TVQJLlKFg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00014

JSON explain

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