SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'd50db82888a8d9d09a24996bbfae928ea12791a22dbac0a26af6e15ad353eb1b' 
  AND token = '4GvFJBP8vGMxPltPEYW/lORl45soXdl15Yf7nq4vTM8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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