SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '62e429c274420c09783520ba9250838e2d2a130558f69de0c0e08fe8b24a63bb' 
  AND token = 'QaPjcUbRxnp+ASkWR1pMXZLvXwGsAys/Mvbz60C3wAQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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