SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34d161eb79a729bd4444c9e4a1f33bc197455d450517184051e574d61f244d10' 
  AND token = '0rVKGGYSLM8pmjH98jLEBQxg4BvUZhF8x6dB6y+ydf0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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