SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '8b1223c46e108b8dc13984ff19da517f7ef791568a4907cf4fe4cf47756043e2' 
  AND token = 'SNonR1zc1im/yD27Bdw7XEMH9zcEsAhPWldoh8aFpv4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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