SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fa8788f7d3b13dab6ff63c11c8277579e9eef740aee1c5dfe02eb01019d80600' 
  AND token = 'GYeTJyOQAJK4yTv/6JBoNm9Gy2Ah/HDSm2V78lgiHao=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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