SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ef6222d43308cea1c7c41a4d3498430f74bbbb4656a935eaad92e22aae3ebf55' 
  AND token = '3Nk1Y9h22JPp4cQckv5wwKIYZGTT/DGZwfH9HpzjSmE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00036

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}