SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ac4938b3658bc3458f84e93baceeb23f52c46e64e7d511ca0aa0724c8bd9087e' 
  AND token = 'POpSMjTngnesFzKDPvuqlYGMS3i+5jLiEii0cpmlwBk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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