SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dfad6dc1477b88a73fdd477e676738268d75a9891e9c82a3187643051d4312f5' 
  AND token = 'n5UAyIq7KOui0r28EnnvDYmmiNfT7kH1ki33r0oxDqE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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