SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a0d8e9a9f886bdad1afd418514b3220f2e4a568b870c4bc467980d943f91f8be' 
  AND token = 'fbjz/wPmr9w2Pz3iaUWENoaQtIFr0My/WHYXhd5v2UM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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