SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aafaad612822d3364078800ac353659b81509a11b58c4691a4a99baeeeed5dc9' 
  AND token = 'bYjVjc78lxK4UCNU6sANleMw44Pw8WrREDtNl8A/kIo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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