SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '24cb9738d675324c196633aeae09be747f6748e106650ce4a69ad9ec187c8bf1' 
  AND token = 'vgeP3yKxtCSkeSwTzTwVMmYaYmpMLSCgz38WBVhi4vI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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