SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb7774b6dcdf1b53075d02372ca7659d6aaeda3848524463b584ce5c05eb01e3' 
  AND token = 'FZrRu9JqPBu4PhNXDUk13bWEvgqpjhb1O41uYSMAQIE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}