SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8c930a16bbc0cb87ae97ce97dc0f38c4d8d2cb58eae44a0b679d061f6706bc6c' 
  AND token = 'ccRqeBurJIzrcDFw5DGBzkTV+YQtuNcn1VxVhP0jl3Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}