SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cd381831a6654e3127eb1c16bb523c5076fa52347a5d6299e363fb04eff45b44' 
  AND token = 'o/xJGOjH124qjiXLm/Z2eSZSYhy3znJNlbZ69esKvOA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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