SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '932ff916743c25e2d94f637311518930529591667cd002753a130edf14aa7d71' 
  AND token = '6G2zpuwtuVQUIwnee4P2FiM0jHpqiIVKVkjozsC7GlM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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