SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6a102b4b16e06340065f3b66738e1f4debcd889b17ddcd9a73bbf021211c9383' 
  AND token = 'ASwF6wYCBUzXRViDfJBAne9t/ZqYU7cg8dnRjJdbC1U=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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