SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6b8bbb1076e72b0b3b493051fb3f52a637dc6b5a0952e1e88412deb9757f9932' 
  AND token = '1LC5Lr/yM/JavLLnVfs2kN2ogrr4YHGrJhEZBkkENo4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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