SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8e14d8608bd2dc7484b7511205b2bf5af0c5e686f3f25c72fb131582092ee3fb' 
  AND token = 'I3fctdhgUpF3ZWJFKA4ohi/YsPnt7oQ/CbxQ3bX+q+M=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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