SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4b08c2339d38465ad6a4e0fd47ebd9ce83ac7ab72735f68690d5dcfec622c5ab' 
  AND token = 'RL4biWuj81uRVegb1mqQJ0x3ClYwjB/vPhH3KlvDH2Y=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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