SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '97ce067db5dd3ac34f9d26ebdfc565760b13a54a3d5ebaebab083bfda9e7224f' 
  AND token = 'YT4jwBd9YgkV8914C3wHG+KdOwNK/GMo8HLzl2/iDrs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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