SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2da0dd629d5d10af863b47002728898489786bd97d928cca41773f0bc5e62f77' 
  AND token = 'LOUI4jyzqVI6wZRMi4DRdfSPyG/P+cfKeRBQtw3yyS8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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