SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '42408222c917c9a1566c676d1d739e78fe2bd9832d1fcf67f9f5b8109ce11559' 
  AND token = 'bZllyPOHlyc5yUPWTx//opEEqgIrZsxvfPuis2mnkXI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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