SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '860868b7e9cc3718a2a22fc2cd5d428014947899367c44abd5b2b6ccf12c5359' 
  AND token = 'jG/o5eZXpOfbsbsU97UqIN70+v+IPvCP2nMCVKSZ6ZU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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