SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5e92945273938a3deaeb72682d4f02b9a14573aafdfade8a106017aff42f0d90' 
  AND token = 'NbCC5FvUpBZ2DNtubnsPzhVSNjnVu+JDOsEXTKNVbbo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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