SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '25e473b7652ebd53669ccc138082ae93a9d734d56f3692e3761434b392c7c13b' 
  AND token = 'DJnhygbuqVRNZSCWsyffmqlM3LlBdcIuN/FgZythK7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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