SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a37175f31102a2b41ecc4a8603a2fe2e9d03dec87c94dcf411b6c310c2b9699f' 
  AND token = '5xVGBhnA5RdjzeYfEKSFjupG2P/Y1AKvEGYEarEQDP0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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