SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6de1a061e0dd7f4cf31aac405b38fdb56f7d1cecdd45483e87e93b572a05394c' 
  AND token = 'U1o1PwD1O+sVHW+IU8ATPbBo75G1MAlGpxshzz7S7HE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

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