SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '3bc172abaf215f097d5c78f6a3e2cb987d93e126d478b5f8ea7fdc31e8064270' 
  AND token = 'EJwMEFAG4u6DE9SYvXWHVDgE1DwbdX4/SBdLlYTQ3aY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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