SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cdb76f15975e7d653f2ace8acdb7018ddfee325ebfea5958d0cc4a631ac467f1' 
  AND token = 'LsYLeEQkNVv884JdumE1q/vs7ncob8V2w4e4w/orXDs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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