SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = 'be75b9d56db54dcdc44d210955eec99ae32f81ef48b323fd6482c527aff892fa' 
  AND token = 'Qv5o9Ri+96QNAa00C5GGAZRjoyevGvuJiSxhJxz2spc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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