SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'ecace8d33a93bd8659644fa9bc0164b45585efca3d4b2142d6b8da652abf403e' 
  AND token = 'FKReSWZRPQvU5shw6fHJrCTW7gijwzv39KTd2wIeBlE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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