SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8601e16291fbc81603392087d0158e8715bb93e8610bfc0e73534ebfe401fb10' 
  AND token = 'ZDz+ObYCXWjbipwph6xeuOOkvs6tHb+f7x8D5idXQYI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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