SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '0cdd9ef587c0ffbdb2173ce8c5104ca9a1406d4ca1298ab0b441fe2caf3dade6' 
  AND token = '1Gt3Nc9U2Y1F91wZ+uvChl2Q53whuIwYO5zqVMimuPU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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