SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0652204d6b7987ed2c786207c79194d753bcbbcc1ac3262a0b8eab0a2b5c3112' 
  AND token = 'EACSJxh+R/XufQ0lzYCpPTjgqmfWQdP8LtBlT9PUH+U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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