SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '19e8c8142f6411e8e54d11f874c8ff8b618df99ed8eb2df97a1b3126b219569a' 
  AND token = 'ZrsL9Num+m2Fx8k2vi2Ck2WfjdAcWGV6AosU0EURmCw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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