SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '974ffdeedfae52021e1685473ea7cb72bb1a47213bf781c6c8704c012057817e' 
  AND token = 'WozBuIfGdn+VXKZXbsUT8yPGdHnWEPh+fXZxicj0MKU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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