SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '89d831146898dc9aca31803c49532bff1db2e0626fbf6cdc0bc0cb113a59d554' 
  AND token = 'i8GNfL2Xg1RuPPJlLy0Rot1yKOQPSgbWVr/vvIZ7syU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00013

JSON explain

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