SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8df6a966330e3e931b92b5a1a2d250446b34a7b85b166e2051d9e4466a85b5d9' 
  AND token = 'w/c47Fto8h043Vr983hcPAqRQpud0NdxaXgSRXr43uo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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